NO. 4.] THE FIRST SUMMER IN THE ICE. 19 



a short point up the shaft. The middle (long) rectrices extend from 12 to 

 15 mm. beyond the others 1 . 



If the plumage of these young birds be compared with the corresponding 

 plumage in other species of La/ridce, there is none that Rhodostethia more 

 closely resembles in this respect than Xema sabini. The distribution of colour 

 is essentially the same in both, particularly in there being dark feathers 

 on the back, with narrow, but clearly-marked, pinkish grey, or greyish white 

 borders. But the distribution of white and black on the wing-feathers is again 

 quite different, and in this respect, Rhodostethia resembles no species of the 

 genera Larus, Rissa, Xema, or Sterna. The black tips of the inner, short 

 primaries (5 to 8), do not quite cover the white part on the underlying pri- 

 maries, whereby an alternating row of black and white spots is produced along 

 the superior border of the folded wing. 



Food, etc. On an examination of the bodies of the specimens which 

 are all preserved in alcohol it appeared that all the birds had been in 

 good condition, and the gizzard, when they were shot, was more or less filled 

 with food. The food consisted exclusively of crustaceans and small fish; no 

 refuse, such as might have been taken from the neighbourhood of the ship, 

 was found. 



As already mentioned, the chief contents of the gizzards were crustace- 

 ans, and in all the specimens, parts of Hymenodora glacialis (Buchh. 1874) 

 could be recognised 2 . Prof. G. 0. Sars, who has kindly determined these 



1 In the large collection of old and young specimens that was made by the Interna- 

 tional Polar Expedition to Point Barrow, in September and October, 1881 and 1882> 

 three young birds (now belonging to the Smithsonian Institution in Washington) are 

 described in detail in the report of this expedition (Report of the International Polar 

 Expedition to Point Barrow, Alaska, pp. 124, 125. Washington. 1885), as they were 

 supposed, from their plumage, to be somewhat younger than the other specimens. In 

 these three specimens, "the middle rectrices are black-shafted, with this color extend- 

 ing more or less on the webs, continuous of the black of the tip". 



In all the 'Fram' specimens, which were several weeks younger, the shaft, above 

 the black tip, was white; in a single specimen, a darker shade extended a little way 

 up from the tip on both sides of the shaft, which itself was white. 



' This ephyrid, which is related to Pasiphae, inhabits exclusively the Arctic Ocean. 

 Professor G. 0. Sars ('The Norwegian North Atlantic Expedition 1876 187a Vol. XIV. 

 Zoology. Crustacea', p. 37, PI. IV. Christiania, 1885) considers this species to be a 

 pelagic form that is not confined to any particular stratum of water; for while the 

 type specimen was taken (during the 2nd German North Polar Expedition) on the very 

 surface of the water in the sea to the east of Greenland, the numerous specimens of 

 the North Atlantic Expedition were taken at various depths, down to 1862 fathoms. 



